I was accused and terminated for driving company vehicle for personal use, which I didn't. I filled it up at a gas station up the road from my house so I wouldn't have to do it the next morning. The supervisor has a personal vendetta against me for a previous incident where I had to call his boss. He discussed the rules for vehicle usage and had me to sign it because he said I hadn't signed one before. I thought it was over, but he called HR and asked them to look through my file and they found a vehicle usage form I signed in '08 upon being hired. When I was hired I drove my personal vehicle for 10 months which my supervisor didn't tell HR.(HR told me this) After my supervisor learned HR had a signed form he asked if I could be terminated and she said yes, which he was waiting to do. The question is,when I received a company vehicle shouldn't they have me sign the vehicle usage form then? Now that they have the signed form (from hire date) they're saying the company has a zero tolerance, but before the form, the supervisor went over the rules and had me sign, as if that was a warning. Can I go the head of HR and present this case?

You may appeal to HR, that is always your right, they do have to prove though some usage that you had it and drove it outside of working hours.

It was after work hours (7pm) The supervisor was fine with that until he learned about the signed form, now he wants to terminate which is not right. Should I appeal ot head of HR?

I agree you can appeal to HR, but if you are in an at will state they can fire you for any reason without having to prove anything (unless its racial or another unlawful reason). As far as when you signed it, the issue is did you have notice of the companies policy on driving and you did if you signed it before the incident. You could look at their policies and see if its listed as a terminatable offense, if it isn't then you can argue to HR that they did not follow their own disciplinary procedures and have a case, but at best you get your job back with lost wages. Unemployment and a new job might be a better outcome,but only you can know that. Good luck.

I am going one step further than adthern, they can fire you for no reason at all if you are not covered by a contract.

Absolutely, they can fire you for any/no reason so long as it isn't based on race or ethnicity, that would be a civil rights violation.

The company also can't single this person out for a violation of policy if other people have violated and not been terminated. Of course, proving that is a whole different story.

Lets think this through, chances are your supervisor can not fire or hire anyone to start with. Supervisors are no where near the top of the chain of command. He may say he wants to fire you just to make you sweat, just sit tight. If HR informs you that you are being terminated ask them for "cause" and see what they say. If they give cause then appeal your termination and briong forth the double standards.